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definitions

ferrugination

[fə-rōō′jə-nā′shən]
n.
  1. Deposition of ferric salts in the walls of small blood vessels, usually of the basal ganglia and cerebellum.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.